Paracoccidioidoma: case record and review

The ulcer resulting from snake-bite injury was characterized by deep and wide tissue necrosis and secondary infection. The patient was at high risk of loss of function of his extremity. From 1989 to 1996, 16 cases with deep ulcer of the upper extremity resulting from snake-bite injury were treated with different types of axial thoraco-abdominal skin flaps, depending on the location of the ulcer. Thoraco-umbilical skin flap was used in 2 cases, lateral thoracoabdominal skin flap in 1 case, iliolumbar skin flaps in 5 cases, lower abdominal skin flaps in 6 cases, lower abdominal divided foliated skin flap in 1 case and Y-shaped hypogastric skin flap in 1 case. Reparative operation was carried out within 3 weeks after injury and primary repair were undertaken in 6 of them. The pedicles were divided in 17 to 24 days after operation. Twelve flaps survived. Three of the 6 flaps had mild signs of inflammation which disappeared after administration of antibiotics. One had necrosis of the distal part of the flap, and was healed with split skin graft. This type of skin flap was an ideal method for the treatment of snake-bite injury of the upper extremity.     

Rat renal allograft tolerance is associated with local TGF-beta and absence of IL-2r expression within chimeric immunocytic foci

Tolerance was induced in Lewis (LEW) rat renal allograft recipients of Brown Norway kidneys by multiple pretransplant donor-blood transfusions and prior limited cyclosporine A. Rat renal allograft tolerance was associated with the induction of systemic donor T cells (10%), an early phase of nonspecific suppressor-cell generation, followed by maturation of systemic antigen-specific suppressor cells, and renal cellular infiltrates that develop long-term in situ in the kidney graft model. It was hypothesized that these infiltrates represent chimeric immunocytic foci that are locally regulated via a TGF-beta-dependent mechanism. Both immunohistochemical staining and digital image analysis for cellular and extracellular TGF-beta, IL-2 receptor (CD25), and the BN Class I-MHC marker (OX-27) were performed. Control rejecting (REJ) kidneys did not demonstrate any differences with respect to levels of infiltrating immunocyte area vs long-term surviving (TOL) kidneys (3.9% vs 4.5%, P = .303). Immunostaining with the BN Class I MHC marker (OX-27) demonstrated high levels of chimerism within immunocyte foci of the tolerant grafts (OX-27 BN+immunocytes 49.0% +/- 5.1%). In situ cellular IL-2 receptor (CD25) expression was demonstrated in REJ kidney infiltrates but not within TOL immunocytic infiltrating foci, when measured as percent of total lymphocytes (REJ = 5.0% vs TOL = 0.4%, P = .031). Conversely, TGF-beta expression was significantly higher in immunocytes of TOL kidneys when measured as the number of DAB chromogen-staining pixels per total immunocyte area (TOL = .076 vs REJ = .047, P = .003). In conclusion, these results suggested that stable mixed immune chimerism (SMIC) plays an important role in DST-CyA-induced tolerance in situ. SMIC-induced tolerance may involve a local TGF-beta-dependent mechanism that is associated with in situ TGF-beta (+) and IL-2r (-) immunocytes.     

Site-directed mutagenesis of the phosphocholine-binding site of human C-reactive protein: role of Thr76 and Trp67

We have reported previously that residues Lys57, Arg58, and Trp67 of human C-reactive protein (CRP) contribute to the structure of the phosphocholine (PCh)-binding site. In this study, based on the three-dimensional structures of human CRP and serum amyloid P, we constructed an additional mutant, T76Y, to probe the structural determinants of the PCh-binding site of CRP. Binding properties of four mutant CRPs, K57Q/R58G, W67K, K57Q/R58G/W67K, and T76Y were compared. Wild-type (wt) and all mutant CRPs were purified by affinity chromatography on PCh-, pneumococcal C-polysaccharide (PnC)-, or phosphoethanolamine-conjugated agarose columns. Purified mutant CRPs, K57Q/R58G/W67K and T76Y failed to bind to solid phase, PCh-substituted BSA. They did, however, bind to immobilized PnC, although with substantially decreased avidity compared with wt CRP. W67K, K57Q/R58G/W67K, and T76Y CRP required a 10-fold higher Ca2+ concentration than wt CRP to bind PnC and exhibited decreased avidity for mAb EA4.1, which recognizes a Ca2+-dependent epitope. We conclude that Thr76 is a determinant of the PCh-binding site, probably interacting with the choline group. This conclusion is supported by recent crystallographic data indicating that this residue participates in the formation of a hydrophobic pocket that constitutes the binding site for choline. Trp67, Lys57, and Arg58 do not directly contact PCh, but appear to be required for the proper conformation of the binding site.     

A statistics primer. Power analysis and sample size determination

Gynecologic-oncologic patients are at increased risk for complications with closed laparoscopy. Open laparoscopy eliminates the steps of blind insufflation and trocar insertion. This study is the first large series of open laparoscopies to assess the feasibility and safety of the open laparoscopy technique in patients with gynecologic malignancies. We performed 90 open laparoscopies in 89 oncologic patients with previous major surgery (65%) and/or radiotherapy (17%) or a large omental cake (18%). Complications due to the laparoscopic access technique occurred in one patient (1%) for whom a laparotomy was performed for a small bowel perforation. The incidence of complications of the open laparoscopy technique (1%) is favorable compared to the complication rate of closed laparoscopy in gynecologic-oncologic patients. It is concluded that open laparoscopy is a safe and feasible technique in gynecologic-oncologic patients.     

Cytoplasmic redox potential affects energetics and contractile reactivity of vascular smooth muscle

Variations in the cytoplasmic redox potential (Eh) and NADH/NAD ratio as determined by the ratio of reduced to oxidized intracellular metabolite redox couples may affect mitochondrial energetics and alter the excitability and contractile reactivity of vascular smooth muscle. To test these hypotheses, the cytoplasmic redox state was experimentally manipulated by incubating porcine carotid artery strips in various substrates. The redox potentials of the metabolite couples [lactate]/[pyruvate]i and [glycerol 3-phosphate]/[dihydroxyacetone phosphate]i varied linearly (r=0.945), indicating equilibrium between the two cytoplasmic redox systems and with cytoplasmic NADH/NAD. Incubation in physiological salt solution (PSS) containing 10 mm pyruvate ([lact]/[pyr]=0.6) increased O2 consumption approximately 45% and produced anaplerosis of the tricarboxylic acid (TCA cycle), whereas incubation with 10 mm lactate-PSS ([lact]/[pyr]i=47) was without effect. A hyperpolarizing dose of external KCl (10 mM) produced a decrease in resting tone of muscles incubated in either glucose-PSS (-0.8+/-0.8 g) or pyruvate-PSS (-2.1+/-0.8 g), but increased contraction in lactate-PSS (1.5+/-0.7 g) (n=12-18, P<0.05). The rate and magnitude of contraction with 80 mm KCl (depolarizing) was decreased in lactate-PSS (P=0.001). Slopes of KCl concentration-response curves indicated pyruvate>glucose>lactate (P<0.0001); EC50 in lactate (29. 1+/-1.0 mM) was less than that in either glucose (32.1+/-0.9 mm) or pyruvate (32.2+/-1.0 mM), P<0.03. The results are consistent with an effect of the cytoplasmic redox potential to influence the excitability of the smooth muscle and to affect mitochondrial energetics.     

The novel cuticular collagen Ovcol-1 of Onchocerca volvulus is preferentially recognized by immunoglobulin G3 from putatively immune individuals

The concentration and affinity to concanavalin A (ConA) of plasma alpha 1-acid glycoprotein (AGP) and AGP levels in extracts of liver tissues were investigated in specific-pathogen-free chickens infected with the highly virulent HPS-2 strain or virulent reference GBF-1 strain of infectious bursal disease virus. The plasma AGP value in uninfected control 3- to 7-wk-old chickens was 161.8 +/- 25.8 micrograms/ml (mean +/- SD), and ConA-unreactive and ConA-reactive AGP comprised 47% and 63% of total AGP. Increases in AGP levels in plasma and liver extracts were observed in both the HPS-2 and the GBF-1 groups, although albumin levels decreased. The plasma AGP values were higher in the HPS-2 group than in the GBF-1 group through the experimental period. In the HPS-2 group, ConA-reactive AGP reached levels 6.8-fold greater than control values and comprised 80% of total AGP at 4 days post-inoculation. In the lipopolysaccharide group, a great increase in ConA-reactive AGP was observed.     

Positional isomers of monopegylated interferon alpha-2a: isolation, characterization, and biological activity

The stereochemistry of beta-oxidation of alpha-methyl-branched fatty acids was analyzed, in rat liver and in human cells, with (2R)- and (2S)-2-methyltetradecanoic acid as model substrates. In rat liver, formation of the alpha,beta-unsaturated compound was found to be concentrated in mitochondria while in human cells, this activity co-distributed mainly with peroxisomal marker enzymes. In both cases, the dehydrogenating enzymes were absolutely specific for the (2S)-enantiomer. In human liver, activation was some three times faster with the (2R)- than with the (2S)-isomer while in rat liver both were activated at about the same rate.